Current wireless mobile communication devices include microprocessors, memory, soundcards, and run one or more software applications. Examples of software applications used in these wireless devices include micro-browsers, address books, electronic mail (“email”) clients, and instant messaging (“IM”) clients. Additionally, wireless devices have access to a plurality of services via the Internet. A wireless device may, for example, be used to browse web sites on the Internet, to transmit and receive graphics, and to execute streaming audio and/or video applications.
Wireless devices are typically supplied with a battery pack, which includes one or more cells forming a battery, for providing power to the wireless device. Such batteries typically include one or more lithium-ion (“Li-Ion”) or lithium-ion polymer cells.
Emerging standards (e.g., IEEE Livium™ 1725 “Standard for Rechargeable Batteries for Cellular Telephones”) for wireless devices such as cellular telephones require that the charging of batteries be inhibited at a given temperature and that the discharging of batteries (i.e., normal use) be inhibited at a somewhat higher temperature. Currently, this function is typically performed by hardware, software, or firmware control means included in the wireless device. Such standards also require that external chargers implement their own independent checks of these temperature limits. Thus, current battery temperature monitoring solutions use hardware, software, or firmware control means within the wireless device and/or external charger to read the battery pack temperature in order to determine whether to begin charging the battery (i.e., if the user wants to charge the battery) and to determine when to stop using (i.e., discharging) the battery.
Now, new chemistry batteries tend to have different charge/discharge limits than those of existing batteries. This can be problematic in that it requires the wireless device and battery charger to correctly identify the battery pack and to include means such as a lookup table to implement the new charge/discharge limits. These requirements increase the processing requirements and hence the cost of wireless devices and battery chargers. This is especially onerous for battery charger manufacturers who try to limit the cost of their devices by, for example, limiting the capacity of processors included in their devices.
A need therefore exists for improved temperature-based charge and discharge control for batteries of wireless communication devices. Accordingly, a solution that addresses, at least in part, the above and other shortcomings is desired.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.